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arXiv · 1505.00405

Highly Retrievable Spinwave-Photon Entanglement Source

Sheng-Jun Yang·Xu-Jie Wang·Jun Li·Jun Rui·Xiao-Hui Bao·Jian-Wei Pan
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Abstract

Entanglement between a single photon and a quantum memory forms the building blocks for quantum repeater and quantum network. Previous entanglement sources are typically with low retrieval efficiency, which limits future larger-scale applications. Here, we report a source of highly retrievable spinwave-photon entanglement. Polarization entanglement is created through interaction of a single photon with ensemble of atoms inside a low-finesse ring cavity. The cavity is engineered to be resonant for dual spinwave modes, which thus enables efficient retrieval of the spinwave qubit. An intrinsic retrieval efficiency up to 76(4)% has been observed. Such a highly retrievable atom-photon entanglement source will be very useful in future larger-scale quantum repeater and quantum network applications.

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Sheng-Jun Yang, Xu-Jie Wang, Jun Li, Jun Rui, Xiao-Hui Bao, Jian-Wei Pan. 2015-05-03. Highly Retrievable Spinwave-Photon Entanglement Source. https://doi.org/10.1103/physrevlett.114.210501

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